By Marcia Dunn

Bulked-up, mutant "mighty mice" held onto their muscle during a monthlong stay at the International Space Station, returning to Earth with ripped bodybuilder physiques, scientists reported Monday.

The findings hold promise for preventing muscle and bone loss in astronauts on prolonged space trips like Mars missions, as well as people on Earth who are confined to a bed or need wheelchairs.

A research team led by Dr. Se-Jin Lee of the Jackson Laboratory in Connecticut sent 40 young female black mice to the space station in December, launching aboard a SpaceX rocket.

In a paper published in the Proceedings of the National Academy of Sciences, Lee said the 24 regular untreated mice lost considerable muscle and bone mass in weightlessness as expected — up to 18%.

But the eight genetically engineered "mighty mice" launched with double the muscle maintained their bulk. Their muscles appeared to be comparable to similar "mighty mice" that stayed behind at NASA's Kennedy Space Center.

In addition, eight normal mice that received "mighty mouse" treatment in space returned to Earth with dramatically bigger muscles. The treatment involves blocking a pair of proteins that typically limit muscle mass.

A SpaceX capsule brought all 40 mice back in good condition, parachuting into the Pacific off the California coast in January. Some of the ordinary mice were injected with the "mighty mice" drug after returning and quickly built up more muscle than their untreated companions, Lee said.

The scientists completed the experiment just as the coronavirus was hitting the U.S.

"The only silver lining of COVID is that we had time to write it up very intensively" and submit the results for publication, said Dr. Emily Germain-Lee of Connecticut Children's Medical Center, Lee's wife who also took part in the study. Both are affiliated with the University of Connecticut.

While encouraged by their findings, the couple said much more work needs to be done before testing the drug on people to build up muscle and bone, without serious side effects.

"We're years away. But that's how everything is when you go from mouse to human studies," Germain-Lee said.

Lee said the experiment pointed out other molecules and signaling pathways worth investigating — "an embarrassment of riches ... so many things we'd like to pursue." His next step: possibly sending more "mighty mice" to the space station for an even longer stay.

Three NASA astronauts looked after the space mice, performing body scans and injections: Christina Koch and Jessica Meir, who performed the first all-female spacewalk last fall, and Andrew Morgan. They are listed as co-authors.

___

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute's Department of Science Education. The AP is solely responsible for all content.

Share:
More In Science
A New Plant-Based Way to Quit Smoking
John Bencich, CEO of Achieve Life Sciences, joins Cheddar Innovates to discuss a new plant-based compound that's being used to fight nicotine addiction.
Plant-Based Way to Quit Smoking; Innovation in Stroke Therapy
On this episode of Cheddar Innovates: CEO of Achieve Life Sciences discusses a new plant-based compound that's being used to fight nicotine addiction; President & CEO OF DiaMedica Therapeutics explains a new ischemic stroke treatment option that expands the window for effective therapy for stroke patients; Cheddar gets a look at Curiosity Stream's 'Asteroid Rush.'
Moderna Seeks FDA Authorization of Omicron-Specific Booster
The pharmaceutical giant Moderna says its updated 'bivalent' booster shot provides a stronger immune response against the Omicron variant of COVID-19 specifically. This week, Moderna plans to submit preliminary data to U.S. health officials in the hopes that its new booster will be available later this summer. Dr. Sampson Davis, emergency medicine physician, joins Cheddar News to discuss.
JWST's Gregory Robinson Expects to See 'Universe Different' in New Images
NASA has announced that the first official full-color images will be beamed back to Earth from the James Webb Telescope on July 12. Gregory L. Robinson, the director of the James Webb Space Telescope Program in the NASA Science Mission Directorate, joined Cheddar News to discuss the anticipated image drop. “We expect to see the universe different," he said. "Webb will allow us to see much, much clearer and deeper into the universe."
Human Evolution Speeding Up; Advancements in Genetic Engineering
On this episode of Cheddar Reveals, Professor Laurence Hurst, Director of The Milner Centre for Evolution, discusses the mystery of human evolution that's still baffling scientists: why are humans still evolving, and why has the process sped up? Neville Sanjana, faculty member at NY Genome and New York University, breaks down the latest innovations in CRISPR genetic engineering and its applications from 'designer babies' to curing genetic conditions and diseases; Cheddar gets a look at Curiosity Stream's 'The Butterfly Effect.'
Editing the Human Genome
Neville Sanjana, faculty member at NY Genome and New York University, joins Cheddar Reveals to break down the latest innovations in CRISPR genetic engineering and its applications from 'designer babies' to curing genetic conditions and diseases.
Why Humans are Evolving Faster Than Ever Before
Professor Laurence Hurst, Director of The Milner Centre for Evolution, joins Cheddar Reveals to discuss the mystery of human evolution that's still baffling scientists: why are humans still evolving, and why has the process sped up?
'Designed to Disappear': Loliware's Seaweed-Based Straws Offer Eco-Friendly Alternative
It can be tough to make sustainable choices, and even harder when sustainable materials don't hold up. Loliware has a solution to the plastic straw problem: its seaweed-based straws are stronger than paper alternatives and once used, can be composted and return to the earth or sea without causing harm. Sea Briganti, CEO of Loliware, joins Closing Bell to discuss the tech behind the straws, new product launches, and more.
Anja Health Raises $4.5 Million to Offer Parents Technology to Freeze Umbilical Cord's Stem Cells for Future Disease Treatment
Umbilical cord blood banking platform Anja Health raised $4.5 million dollars in a seed round led by Seven Seven Six, a venture capital firm founded by Reddit co-founder Alexis Ohanian. Anja Health offers a personalized, doctor-backed cord blood bank, which lets new parents freeze stem cells from their child's umbilical cord so they can be used to treat diseases in the future. It's a process Anja has called 'Hollywood's best-kept secret,' as celebrities like Kylie Jenner, Serena Williams, and more have all banked their umbilical cord blood. Kathryn Cross, the founder of Anja Health, joins Cheddar News' Closing Bell to discuss.
Load More